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arXiv · 2205.12218

The excitation spectrum of two dimensional Bose gases in the Gross-Pitaevskii regime

Cristina Caraci·Serena Cenatiempo·Benjamin Schlein
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Abstract

We consider a system of $N$ bosons, in the two-dimensional unit torus. We assume particles to interact through a repulsive two-body potential, with a scattering length that is exponentially small in $N$ (Gross-Pitaevskii regime). In this setting, we establish the validity of the predictions of Bogoliubov theory, determining the ground state energy of the Hamilton operator and its low-energy excitation spectrum, up to errors that vanish in the limit $N \to \infty$.

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Cristina Caraci, Serena Cenatiempo, Benjamin Schlein. 2022-05-24. The excitation spectrum of two dimensional Bose gases in the Gross-Pitaevskii regime. https://doi.org/10.1007/s00023-023-01278-1

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